The yearbook/annual for the University of Wyoming is titled the "WYO." In general the yearbook was published from 1909 until 1989. There are some years when no yearbook was published. The university no longer produces a yearbook. The last publication of The Wyo was in 1989.
In addition, the UW Libraries hold yearbooks for the UW Lab School / Preparatory School.
The quickest way to view the yearbooks is through the UW Libraries' Digital Collections.
This link will display the yearbooks. The yearbooks may be browsed online or downloaded as a pdf.
Many volumes are digitized and are available for online viewing and download on the Internet Archive webpage. Other digital copies from the Internet Archive are available here.
Print copies are available in the Level 3 stacks. The call number is LD6268.W86.
Print copies are also available in the Emmett Chisum Special Collections on Level 3 of Coe Library. The call number is the same. These copies must be viewed in the Chisum Reading Room.
Select copies of the WYO are located in the McMurry Family Reading Room on the west end of Level 2 of Coe Library.
The UW LIbraries do not have copies of the 1935, 1936, 1937, 1938, and 1939 WYO yearbooks. It is believed that no yearbooks were published those years due to the Great Depression, but there is no note in the 1940 yearbook that specifically answers the question whether yearbooks were printed or not.
There are no yearbooks available for 1978, 1979, 1980, and 1981, although there was a special "Graduate Students" yearbooks published in 1980. In addition, the 1977 yearbook is significantly shorter in length than previous and following years. There is a note in the 1982 yearbook that states no yearbooks had been published since 1977. The yearbook staff added a few pages with information about significant UW events for the missing years, but there is not any information about individual students from those years.